1. Field of the Invention
The present invention relates to a camera which can deliver both an ordinary color picture and spectrum analysis data, a spectrum analysis system, and a combustion evaluation apparatus which employs them.
2. Description of the Related Art
In a case where a camera employing a CCD (charge-coupled device) or the like is applied to spectrum analysis, only light of a desired wavelength is measured by externally mounting a filter on the camera. In the case of analyzing a spectrum at a plurality of wavelengths, or in the case of requiring an ordinary color picture, a plurality of filters and cameras are used.
An example in which the camera is actually used for spectrum analysis in this manner is a video system for analyzing the spectrum of flames in a gas turbine combustor as disclosed in Japanese Patent Application Laid-open No. 3-207912.
The prior art, however, has the following problem. In the case of changing between the plurality of filters in use, a mechanism for driving the filters is necessitated which incurs the problem of a complicated structure.
It has also been considered to use separate cameras for the respective filters. In this case, however, the operations of determining positions and angles for photographing, focusing the cameras, etc., must be performed in correspondence with the number of cameras in use. This poses the problem that a rapid measurement is impossible. Especially in the case of spectrum analysis, all the cameras need to be focused on an identical location, resulting in very difficult handling.
Another problem is that the system becomes costly.